Panasas Debuts SSD-Accelerated ActiveStor 14 NAS Arrays

Posted on September 17, 2012 By Pedro Hernandez

Panasas today took the wraps off ActiveStor 14, a new line of hybrid storage systems that is the result of applying some of the lesson imparted by company's high performance computing (HPC) storage legacy to today's storage challenges.

Panasas "focused on scale-out NAS appliance for big data workloads," during the development of the ActiveStor 14 system, says Geoffrey Noer, senior director of product marketing. And while Panasas is getting on the solid-state drive (SSD) bandwagon for the fifth generation of ActiveStor, Noer says that the company's approach to SSD acceleration hinges on "adopting flash memory in the most appropriate way."

For ActiveStor 14, SSD is "not a bolt-on," says Noer. The "inherent, fully integrated SSD" in each of the company's storage blades is incorporated alongside SATA disk storage. The Panasas file system and management software takes a similar approach in presenting both SSD and disk SATA storage in a single, easy to manage pool.

As it turns out, finding an appropriate role for SSDs in Big Data workloads means thinking small. The company accelerates NAS operations by placing small files and metadata and SSDs. Why this focus on small files and not big ones?

Noer says that Panasas took "a look at the workloads that customers have." And despite their claims -- many "say that they are all about large files," reveals Noer -- the company discovered that their workloads are decidedly more mixed. Not only were there small files in abundance, but they also slow down file operations.

By taking these real world workloads into account, Panasas developed a system that automatically keeps smaller files on SSDs. Using this strategy, ActiveStor not only assures rapid file transfers of sub 60 KB files, but also that those small files don't compete with larger files for disk resources.

Similarly, by storing all metadata on SSDS, ActiveStor 14 eliminates a bottleneck in traditional NAS architectures where "both the data and the metadata are going through the same filer head," informs Noer. To further improve performance, the first 12 KB of every file is stored in metadata.

The result, according to Panasas, is a more responsive file system and directory listings that populates in a snap. The architecture also helps the system deliver fast I/Os and near-linear scaling to 8 petabytes (PB) and 150 GB per second.

So far, the company's benchmarks bear out its claims. One 27-drive ActiveStor 14T shelf delivered 20,745 operations per second (SPECsfs2008_nfs.v3), a response time of 1.99 milliseconds and 768 ops/s per data drive in SPEC SFS tests. Two shelves bumped the score to 41,116 operations per second and improved response times to 1.39 milliseconds.

And in a move that should please storage administrators, RAID management and performance also got some attention. Panasas says that improvements include 30 percent to 50 percent faster RAID reconstruction rates and a lowering of parity RAID overhead from 11 percent to 3 percent.